I didn't watch the vid, taking to long to start... trying to picture what was done and it should work well..."back in the day" when I was changing tires/tubes often I used a piece of old tubing as a cushion of the tool to rest on without marring the rim... worked rather welll from what I can remember!
Yes, once you've all picked yourself up from the floor after falling out of your chairs from reading that... I "DID" work on my own bikes... back when that is ALL i had going for me... not saying it was a bad thing but it was all I did. If and/or when I get into it again to that level that part of me may reappear...